Does the skirt specifically have to fit the hole ? I thought it was just flat oversized rectangular piece of thin rubberised material with a slot for the saildrive leg that was glued in place where it met the surrounding hull. In that respect I've heard of some boats that have in the past lost theirs, a fact that did not get discovered until next time the boat was lifted out, so I don't think it's critical to fit a specific shape, just that it should cover the hole.